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31.
正常闪光视网膜电图的频域分析 总被引:3,自引:0,他引:3
应用快速傅里叶转换技术对正常视网膜电图进行频域分析,发现其a、b波的优势频及能量集中在5-75Hz;与OPS波的分离点为77HZ,从而提出单纯记录a、b波及OPS波各自的较理想的通频带。 相似文献
32.
汽车驾驶员心电多相频谱分析 总被引:2,自引:0,他引:2
对117例汽车司机应用HBD-1心电多信息诊断仪进行心电多相频谱分析,其功率谱,传递相移,幅度直方图等五项指标总分阳性率明显高于对照组,随着驾车年限的增加,总分阳性率有升高趋势,心电频谱分析对230例冠心病病人阳性检出率84.78%。研究认为汽车司机是易发高血压,冠心病的危险人群,该方法在冠心病的环境流行病学研究中具有重要的临床,亚临床意义。 相似文献
33.
抑郁障碍患者人格特征与发病关系的研究 总被引:7,自引:3,他引:4
目的探讨抑郁障碍患者的人格特征与其疾病发病间的关系。方法采用自评抑郁量表(SDS)、艾森克人格问卷 (EPQ)、应对方式评定量表 (WCRS)和归因方式问卷 (ASQ)对 76名抑郁障碍患者进行测试 ,同时选取 84名健康被试进行对照研究。结果①抑郁组患者在EPQ中神经质 (N)与精神质 (P)的得分显著高于健康组。②WCRS的结果显示在“宣泄接纳”、“退避调节”两个因子上 ,抑郁组的平均得分低于健康组。③在ASQ的得分中 ,抑郁组在负性事件归因的自身性、持久性和整体性均显著高于健康组。④抑郁障碍患者的“神经质”人格特质与应对方式的“宣泄接纳”和“退避调节”因子呈负相关 (r = 0 .474)。结论抑郁障碍患者的人格特征可表现为较强的神经质及孤僻、交往障碍 ,他们这种人格特征及应对和归因方式在其发病过程中起着重要作用。 相似文献
34.
Background: Melatonin is gaining popularity as a sedative agent with children. This study sought to characterise this practice more precisely as well as examine aspects of its safety and efficacy in order to develop treatment guidelines.
Method: Postal surveys of two groups of psychiatrists: generic child psychiatrists and psychiatrists who regularly treat learning disabled children.
Results: Both groups (all of the specialists and 81% of the non-specialists) reported regular but not frequent use of melatonin in their usual practice, mostly for night-settling sleep problems refractory to behavioural modification strategies, commonly in the context of neurodevelopmental disability (especially autism). Treatment was described as being 'usually successful' and side-effects were highly infrequent and mild in nature. Variations in most prescribing practices were identified (dosage, timing).
Conclusions: Melatonin appears to represent a useful and relatively safe drug when used in specific circumstances; however, the evidence-base underpinning its use, particularly over the long-term, remains modest. Thus caution and clinical audit of practice is required. 相似文献
Method: Postal surveys of two groups of psychiatrists: generic child psychiatrists and psychiatrists who regularly treat learning disabled children.
Results: Both groups (all of the specialists and 81% of the non-specialists) reported regular but not frequent use of melatonin in their usual practice, mostly for night-settling sleep problems refractory to behavioural modification strategies, commonly in the context of neurodevelopmental disability (especially autism). Treatment was described as being 'usually successful' and side-effects were highly infrequent and mild in nature. Variations in most prescribing practices were identified (dosage, timing).
Conclusions: Melatonin appears to represent a useful and relatively safe drug when used in specific circumstances; however, the evidence-base underpinning its use, particularly over the long-term, remains modest. Thus caution and clinical audit of practice is required. 相似文献
35.
测试了3种新型L-品红成色剂的应用性能。结果表明:与母体品红成色剂相比,L-品红成色剂能显著地减少在蓝光区的有害吸收;与工业用油溶性品红成色剂Ns相比,L-品红成色剂的一些照相性能更加优越。 相似文献
36.
37.
W. N. Charman 《Ophthalmic & physiological optics》2006,26(1):5-12
In the Cardiff acuity test, simple pictures on an otherwise neutral grey card are defined by borders consisting of a relatively broad white band flanked by black bands each half the width of the white band. Higher levels of acuity correspond to the ability to detect figures defined by narrower borders, the figure size remaining constant. It is sometimes implied that the acuity limit corresponding to each card can be equated with different levels of grating resolution, the total width of the border corresponding to the overall grating period. It is shown that although the spatial frequency spectra of the Cardiff figures, like those of other vanishing optotypes, lack very low-frequency components, they have a complex two-dimensional form. The figures have wide spatial bandwidth and no well-defined discrete frequency components. As a result, the relationship between measured Cardiff and grating acuity will vary somewhat, depending upon the particular optical, neural or other deficits of the individual being tested. 相似文献
38.
39.
P Bebbington 《Acta psychiatrica Scandinavica》1987,75(6):640-650
Data are presented from the English national statistics for first admissions with affective disorders during the years 1982-1985. Overall rates per 10(5) of the population aged over 15 years were 36.1 for men and 59.1 for women. The peak incidence for depressive neurosis was middle adulthood, that for affective psychosis much later. The widowed and divorced showed much higher rates than the single and married for all types of disorder. Marriage appeared less protective for women than for men. The age-incidence relationship among the divorced and widowed was exaggerated for depressive neurosis and reversed for psychosis. The results are interpreted in terms of a (possibly biological) releasing effect of age upon affective psychosis that could be overwhelmed by severely adverse social circumstances. The findings support the validity of the distinction between affective psychoses and depressive neurosis. 相似文献
40.
Serum and red blood cell folate in depression 总被引:2,自引:0,他引:2
Serum folate concentrations were estimated in patients with major depressive disorders, lithium-treated patients, detoxified alcoholic patients and normal controls. Red blood cell (RBC) folate concentrations were also estimated in subgroups of patients with major depressive disorder and normal controls. Results showed significantly lower serum and RBC folate concentrations in patients with major depressive disorder than in normal controls. Lower serum folate concentrations were associated with greater severity of depression. There was no association between serum and RBC folate concentrations and endogenicity of depression or the presence of weight loss. 相似文献